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How to fetch the row count for all tables in a SQL SERVER database [duplicate]
...n be used to determine if there is any data (i.e. row count) in any of the tables of a given database.
13 Answers
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How to select rows with no matching entry in another table?
...ication and I've discovered that, joy of joys, even though values from one table are being used in the style of foreign keys, there's no foreign key constraints on the tables.
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Howto: Clean a mysql InnoDB storage engine?
...clean a mysql innodb storage engine so it is not storing data from deleted tables?
2 Answers
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Adding a new SQL column with a default value
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Try this:
ALTER TABLE table1 ADD COLUMN foo INT DEFAULT 0;
From the documentation that you linked to:
ALTER [ONLINE | OFFLINE] [IGNORE] TABLE tbl_name
alter_specification [, alter_specification] ...
alter_specification:
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Create table using Javascript
I have a JavaScript function which creates a table with 3 rows 2 cells.
12 Answers
12
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Check if a temporary table exists and delete if it exists before creating a temporary table
I am using the following code to check if the temporary table exists and drop the table if it exists before creating again. It works fine as long as I don't change the columns. If I add a column later, it will give an error saying "invalid column". Please let me know what I am doing wrong.
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MySQL Conditional Insert
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If your DBMS does not impose limitations on which table you select from when you execute an insert, try:
INSERT INTO x_table(instance, user, item)
SELECT 919191, 123, 456
FROM dual
WHERE NOT EXISTS (SELECT * FROM x_table
WHE...
ERROR 1452: Cannot add or update a child row: a foreign key constraint fails
I have created tables in MySQL Workbench as shown below :
21 Answers
21
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Search an Oracle database for tables with specific column names?
We have a large Oracle database with many tables. Is there a way I can query or search to find if there are any tables with certain column names?
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When should I use a table variable vs temporary table in sql server?
I'm learning more details in table variable. It says that temp tables are always on disk, and table variables are in memory, that is to say, the performance of table variable is better than temp table because table variable uses less IO operations than temp table.
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